The present invention relates to a desalting method for nutritional supplements with animal protein, and a regenerating method for the ion exchange resin used in the desalting method, whereby the nutritional supplement can be provided in low salt with relatively low loss of animal protein and the ion exchange resin can be regenerated again after the desalting process.
Chinese have a traditional idea that food is better than medicine to nourish the bodies. Though most people can get a lot of nutrition from foods provided in the regular meals at the present days, they, especially Chinese and those after operations, illness, and childbirth, like to take nutritional supplements between the regular meals for increasing their energy, vigor, and building up their resistance to disease.
In the past, people would stew meat together with herbs to prepare nutritional supplement by themselves. However, most modern people usually don""t have time to do the preparation of such nutritional supplements by themselves because they are busy due to work and because the preparation and stewing of the nutritional supplements takes a long time. Therefore, canned nutritional supplements have been made available in the market by food companies for customers to have them easily. Such canned nutritional supplements mainly contains animal protein, and are usually provided in a condensed form such that same can nourish the takers in an efficient way.
However, such nutritional supplements are found to have a disadvantage that they contain relatively much salt that is not healthful for the takers, especially those who suffer from high blood pressure, and illness on kidney, heart, and cardiovascular.
Therefore, many food industries have been focused much attention on developing low-salt nutritional supplements that most people can take. One method for desalting the nutritional supplements is by means of ion exchange. The ion exchange resin used in such ion exchange method would also absorb some part of the animal protein, thus reducing the main nutrients of the food supplements.
Therefore, it is a main object of the present invention to provide an ion-exchange desalting method for nutritional supplements with animal protein such that the animal protein loss in the desalting process can be reduced to an ideal degree.
It is another object of the present invention to provide a regenerating method for the ion exchange resin used in the desalting method such that the ion exchange resin can be used again.
The ion-exchange method for desalting nutritional supplements includes:
(1) stewing animal tissues under high pressure to make the semi-product of the nutritional supplement;
(2) passing the semi-product in a first direction through a first column, and a second column in sequence, which contain resin with strongly acidic cation, and resin with strongly basic anion respectively; thus, the cation (including Na+) in the semi-products are exchanged for the hydrogen ions (H+) in the resin of the first column, while the anions contained in the semi-products are exchanged for a hydroxide ions (OHxe2x88x92) in the resin of the second column;
(3) Concentrating the nutritional supplement, of which most of the salt ingredient is removed.
The regenerating method for the ion exchange resin used in the above desalting process includes:
(1) passing water through both columns to wash out the protein residues in a second direction opposite the first one; precipitating and recovering the protein residues;
(2) passing NaOH solution through the first column containing the resin with cations; passing water and HCL solution through the cation exchanger in the first column in the first direction separately;
(3) passing water through the cation exchanger in the first column in the first direction, and then in the second direction;
(4) passing HCL solution through the second column containing the resin with anions; passing water, and NaOH solutions, in the first direction, through the anion exchanger in the second column separately;
(5) passing water through the resin in the second column in both of the first and the second directions separately. Thus, the resin in both of the columns can be used again.